DISEASE CHARACTERISTICS:

• Diagnosis of multiple myeloma

  • Relapsed or refractory disease
• Must have received no more than 6 courses of vincristine, doxorubicin hydrochloride, and dexamethasone (VAD) or VAD-like therapy (e.g., VAMP, CVAMP, or Z-Dex)
• Measurable serum and/or urine paraprotein, or serum free light chain
• No nonsecretory disease

• Patients must meet 1 of the following criteria:

  • Received an autologous transplantation in the past year and received no more than 1 prior line of therapy
  • No prior autologous transplantation, achieved ≥ partial response with prior VAD therapy, and received not more than 2 prior lines of therapy
  • Achieved minimal response, no change, or progressive disease with prior VAD therapy, and received ≥ 2 (if no change or progressive disease) or 4 courses (if minimal response) of VAD or VAD-like therapy

PATIENT CHARACTERISTICS:

• ECOG performance status 0-3
• Serum bilirubin < 1.5 times upper limit of normal (ULN)
• Serum ALT and AST < 2.5 times ULN
• Platelet count ≥ 75,000/mm³
• Absolute neutrophil count ≥ 1,000/mm³
• Serum creatinine ≤ 400 μmol/L
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception
• Peripheral neuropathy or neuropathic pain < grade 2 as defined by NCI CTCAE v. 3.0
• Cardiac ejection fraction ≥ 40% by ECG or MUGA scan
• No pericardial disease
• No acute diffuse infiltrative pulmonary disease
• No known HIV seropositivity
• No known hepatitis B or C infection
• No prior or concurrent malignancies at other sites, except appropriately treated localized epithelial skin or cervical cancer, or other cancer from which patient has been cured and disease-free for more than 5 years
• No medical or psychiatric condition that, in the opinion of the investigator, contraindicates the patient's participation in this study

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No plasma exchange within the past 21 days
• No prior bortezomib therapy
• No more than 1 prior autologous transplantation
• More than 4 weeks since prior and no concurrent use of any investigational drug
• No other concurrent antineoplastic therapy, including thalidomide and derivatives
• No concurrent COX-inhibitors